Herbicidal composition



Patented Oct. 28, 1 952 New York v v No Drawing, Application May. 8, 1947,

' Serial No. 24=6,86 2 5 7 l 7 1 I 40m n (o1.11-2.7")-

invention relates to tions and more specifically pertains to the use of bis-alkylxanthogens and bis-alkylthioxanthogens as the toxic ingredients in horticultural compositions which are exceedingly efiective as herbicities. l I

e have discovered that bis-alkylxanthogens and bis-alkylthioxanthogens having the generic formulawhere R is an alkyl hydrocarbon radical, Y is oxygen or sulphur and'x is an integer greater than 1, but less than 5, are excellent herbicidal compositions being eifective in solutions or aque-' ous emulsions containing as little 'as only 0.5% by weightfofsaid xanthog'ens or thioxanthogens." These'compositions have been used against the plant life usually found in driveways, tennis courts, roadsides, vacant lots, drainage ditches, barn lots, etc. as for example crab-grass, foxtail, ragweed, lambsquarters, oxalis, quack grass,

plantaimburdock, Japanese honeysuckle, dande-' li on ,'shepherds purse, poison ivy, Canadian thistles and bindweed, with much success; fIn

factall plant lifecan be successfully destroyed by the use of these chemical compounds as'hereinafter described.

As an example of. the bis-alkylxanthogens and bis alkyithioxanthogens,-- which are useful according to our invention, there are, among others, where in the above formula Y is oxygen and a: is 2, such compoundsas bis-ethylxanthogen,

bis-.n-propylxanthogen, bis-isopropylxanthogen, and bis-methylxanthogen; where Y is sulphur and m is 2, such compounds as bis-ethylthioxanthogen, bis-n propylthioxanthogen, bis isopropylthioxanthogen, and bis-methylthioxanthogen; wherethiox'anthogen disulfide, bis-methylthioxantho-'- gen disulfide, bis-cyclohexylthioxanthogen disultide and bis-benzylthioxanthogen disulfide.

The following examples illustrate the efiectiveness of the bis-alkylxanthogens and bis-alkylthioxanthogens as destroyers of plant life.

herbicidal composi- 5 Y kers, N. Y.,' assignors to The B; F. .LGoodrich Company, New York, N. I a corporation of Ewa'mple'Ifi V A .plotof mixed weedsfand 'gras'sesji'about 10 feet square. consisting niai'nl'yflof' quack'f'grass, plantain and dahdelionwas sprayed withja coinposition made up by dissolving 0.09 part by Weight of bis-isopropylxanthogiir v in' 1.75 parts byf weight of a refined deodorized kerosene and dis-j persing this solutionin 16.5 parts by weight 'of water with 0.18' part of a mixture of sodium salts of the sulfated fatty'alcohols having IO'to lii'carf bon atoms sold under the name ofAquarex'Di Itf was observed that all the quabklgrassaridjBO'Z, of the other grasses were after treatment.

Example I]- Another .plot of weeds and, grasses containing predominantlythe sametype'of weeds aswer'e'in the plot treated in Example I was sprayed with an aqueous emulsion containing 1% by weight of bis-isopropylxanthogen and 1 about 0.125 'lby' weight of the mixedsodium salts ,of sulfated f tty alcohols having 10 to 18 carbon atoms soldiunderthe name of Aquarex D was us'ed as an emulsifya ing agent. It was observed,-five"tosevendays after treatment, thatv mostall of the 'plantilife was deadfl Example III A heavy growth of Japanese honeysucklewas sprayed with a solution containing 5% of bis- -iso-' propylxanthogen dissolved in an insecticidegrade' of refined kerosene. -A similar patch of Japanese honeysuckle was sprayed-with an aqueousemul-v sion containing 5% bis-isopropylxanthogen emul-l sified with 0.3% of Aquarex 'D.; Itwas observed that the foliage and stems of theplants blackened in about five days and that all the plants were dead in seven days. In about fourteen days anew crop of Japanese honeysuckle-had begun to show, but these new plants died within a few --days. This residual effect was probably due to a delayed action on the underground plant system'rather than a resulting soil sterility, for othenpiants that had not been present when the herbicidal compositions were applied-had started and con? tinued to grow.

Example-IV; a

' A portion of a plot of an accumulation of-weed growth on the edge of a field along a fence row was sprayed with a 5% solution of bis-isopropylxanthogen dissolved in an insecticide grade of refined kerosene. Another portion was sprayed,

with an aqueous emulsion containing 1% of bisisopropylxanthogen. The accumulation of weeds included such commonly found weeds as crabgrass, foxtails, ragweed, lambs-quarters, oxalis, quack grass, plantain, burdock, Japanese honeysuckle, dand'elion lgshepherds purse', poison ivy;

Canadiari-:-thistle -and bindweed. each weed plot sprayed, the kill of the plants was complete in seven days, and even after fourteen days it was noted that regrowth of the plants was nearly.

completely retarded.

When solutions and aqueousemulsions of hisethylxanthogen disulfide wereieinployd in plant. destroying compositions in substantially thesame.

tests as described above, the results were found to be essentially the same.

4 higher concentrations can be employed if desired, but by employing such compositions containing more than 5% of the xanthogens and thioxanthogens, the final results would be no different, while the cost of application would be increased; beyond .that considered "economically sound. J) 3 :9 ."V

While we have disclosed specific examples of J our invention, we do not desire or intend to limit ourselves solely thereto for as hitherto stated, other'equivalent chemical compounds can be employed and the proportions of the active ingredientsmay' be, varied if desired Without depart- The other bis-alkylxanthogens andbis-alkylxanthogen disulfldes as well as the bis-alkylthioxanthogens and bis-alkylthioxanthogen disulfides enumerated above may be used in the same mannor as described in the: above specific examples with aboutthesame results.

hereinbefore illustrated, vaqueous emulsions and ldispersions ofi, bis-'alkylxanthogens and bis-- alkyltliioxanthogens, prepared without" the use of dispersing or wettingagents are equally as efiecti'veas those prepared with wetting .or dispersing agents; M In all probability the use of .aqueous emulsions or dispersions would be preferred for' air-genes s, applica pavedlroads land di age teaches. .bar'n'y lots etc. For these purposes, .aqueous' d is ersions of bis-alkylxanthogens and "bis-alkyl'thioxanthogensmay be prepared with such dispersing or wetting'agents as, for example, those typifiedbythe following general classifications: sodium and potassium salts ofidtty'acids 'knowrra's' soft and hard soaps; salts n fon L highway berms, un-

of Z di'sproportionated"abietic"acid 'known as rosin so'apsf salts of the hydroxy aldehydeacids present i r'rseaweed known; as algin' soaps; alkali-casein compositions;.water=so1uble' lignin sulfonate salts; long chainalcoholsusualIY containing 1D to I8fcarbon a'toinsgwater-soluble salts of sulfated fattyalcohols containing 1 0 to '18 carbon ato'msiwater soluble'saltsof siulfated fatty acid amides; water-soluble esters of sulfated fatty acids; water-soluble alkyl sulfonates having-on the average of 16.:oarbonatoms in the alkyl group; water-soluble aryl sulfonates; water-solu- 1 blef' alkyl arylsulfonats; water-soluble aralkyl sfulfonatesi water-soluble sorb'i'tan' mono-laurate; palini'talte, '-stearate;-}and- -ole'at'e and' othersl: Th'ese dispersingand wetting agents -are sold an der' numerous trade names and' may be either pure compounds or be mixtures .of compoundsfof: I thsarne general group;

ployed to disperse or emulsify: the. bissalkylxanth'oge'n or bis-'alkylthioxanthogen, .it will" be; usually:-necessaryz.tosuse' aqueous. solutions con-5 tainingiorily'fromiabout A l to about 5% of the? wetting; orrdispersing-qagent: to. prepare compositionsecontaining:v from about 0.05 to: about 5% of l these-herbicidalcompositions;-

Although the {USE aof thepreferred concentra tions of .05%;;to; about 52% of these-herbicidal materials has been described in the specific examples, the disclosure of these specific quantities is not intended as alimitationof the use of these materialsafor: it will be .readily. understood that ways. tennis courts," drain When a wetting or dispersing agent is em ingtfrom' therspirit and scope of our invention as defined in the appended claims.

We claim:

ILA methodof' killing plant life which comprises uniformly applying to the foliage of living plants a composition containing as the essential active ingredient from about 0.05% to about 5% by; weight of -.bisz isopropylxanthogen havin -1 the formulas '1. 1

a. A imethod of kmmg plant life which com prisesuniforrnly applying to the foliage of living plants a lethal concentration of bissisopro121511 xanthogenhavingtheformula:

\ oHroH-o-c s-soo on;on1j ta. t tea WILLIAM n:- STEWART? emulsifiedin an. aqueous inediunn JOHNHJSTAI lDENf] REFERENCESLCITED I The-following references are of record'- inthe= file-'of- 'tliis-pa entt" .UN-ITED S'IH KIZE'S.i PA'I NIZi1. v

' Datea I OTHER R FER NCES v Roark etia-L, Listof Organics Compounds-- Used asjnsecticidesfl "U. S. Dept. of 'Agr: Bur, of; Entom, and Plant Quan, Div of Insect invest @344, pages 378,179, May, 1935. 

1. A METHOD OF KILLING PLANT LIFE WHICH COMPRISES UNIFORMLY APPLYING TO THE FOLIAGE OF LIVING PLANTS A COMPOSITION CONTAINING AS THE ESSENTIAL ACTIVE INGREDIENT FROM ABOUT 0.05% TO ABOUT 5% BY WEIGHT OF BIS-ISOPROPYLXANTHOGEN HAVING THE FORMULA 